The present invention relates to a control method of a storage device system, a computer, and a storage control device.
In recent years, in order to move with rapid advances in information system technologies, a chance increases of subcontracting intra-company information system handling work—such as system design, management, and maintenance services—to outside business entities such as a corporate data center or the like. This practice is known as the outsourcing.
Here, in many cases in the data center or the like, a previously used or “old” storage control device such as a file server or the like which has been conventionally used is directly transferred from a service user or subscriber (business company or organization of the outsourcing request source or client), for handling a storage device system (storage system) which is made up of a group of old storage control devices on a per-subscriber basis.
Note that such the storage device system is typically arranged in one form of a distributed database system. An example of this distributed database system technology is disclosed in JP-A-08-305723, which suggests a method for storing image data in a distributed database rather than storing an integrated version of the image data.
Incidentally, the old storage control device stated above is designed under an assumption that this device is used from a computer that is connected thereto via the service subscriber's installed local area network (LAN) so that the storage control device inherently lacks any mechanism which permits common shared usage among different service subscribers and among an increased number of unspecified users. Due to this, in the data center or the like, a need is felt to install and set up old storage control devices in units of service subscribers. This would result in an unwanted increase in installation space within the data center and also an increase in handling and maintenance costs.
On the other hand, in the recent years, the storage control devices including but not limited to disk array apparatus are becoming more greater in storage capacity and higher in performance. Under this circumstance, in the data center or the like, in order to cope with the above-noted increase in installation space and maintenance cost, it is required to effectively handle and manage the group of old storage control devices in units of service subscribers while at the same time letting them be integrated together into a new storage control device with larger storage capacity and higher performance.
Here, consider one case where a network attached storage (NAS) is implemented as the above-noted new storage control device. The NAS is designed to have a built-in file system to be LAN-connected for use, such as the Network File System (NFS), Common Internet File System (CIFS), or Direct Access File System (DAFS). In this case, NAS is operable to manage files which have been moved (duplicated) from more than one old storage control device by utilizing the common sharing function of the file system that the NAS owns by itself; however, in such case, a need arises to consolidate or unify the management of those files in which management information is written (referred to hereinafter as management information files) such as “/etc/exports” files of a UNIX (registered trademark) based operating system (OS) or else.
Due to this, in cases where setup errors occur in the course of registration and maintenance of the above-noted management information files, its influence spreads and impacts upon the entirety of a host computer which acts as a service providing destination of the NAS. Additionally, since the NAS takes a system form to be directly coupled to the network of interest, it can easily receive unauthorized access from the outside while simultaneously suffering from risks of leakage of the management information files. To be brief, from a view point of service continuity and security reservation, in the data center or the like, any attempt is not made to integrate the old storage control devices such as file servers, resulting in increases in installation spaces within the data center and in handling/maintenance costs.